The present invention relates to photographic units, particularly electronic flash units, provided with means for determining the numerical values of camera settings to be established for the making of flash exposures.
Flash units of the general type in question are often provided with a so-called diaphragm calculator. Typically, the so-called diaphragm calculator comprises two calibrated scales, one for the diaphragm setting and the other for subject distance. These two calibrated scales are typically mounted for relative shifting movement in dependence upon the preliminary setting of the camera for the sensitivity of the film to be employed. Very often, the two calibrated scales are provided on rotatably mounted disks or sliders mounted on the exterior of a wall of the flash unit housing.
It has been found that, for persons not familiar with the manner in which the settings of a photographic camera are to be selected for flash exposures, the correct selection of the settings and the reading and interpretation of the selected settings is difficult and confusing. This is due, in the first place, to the fact that the amateur photographer is presented with a large number of numerical values (up to twenty) inscribed on the various adjuster elements and/or cooperating calibrated scales; very often, the amateur photographer does not completely understand the meanings of these numerical values, in themselves, nor the interrelationships among them. Furthermore, because modern flash units are typically of small dimensions, the so-called diaphragm calculators provided on them are usually of correspondingly small dimensions, so that the various numerical values inscribed on the components of the diaphragm calculator are very small and hard to read, and crowded together in a small space.